L-92-224, Forwards Response to Rev 2 to NRC Safety Evaluation, Transmitted Via Re Relief Request Anomalies in Inservice Testing Program.Description of Process Used in Developing Inservice Testing Program Also Encl
| ML17227A554 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 08/12/1992 |
| From: | Sager D FLORIDA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| L-92-224, TAC-M74794, NUDOCS 9208180198 | |
| Download: ML17227A554 (24) | |
Text
.ACCEI ERATED DJCTRIBM'ION DEMOIXISTyIxxTION SYSTEM REGULAl Y'NFQRNATXQN DXSTRXBUTXQN SYSTEN (RIDS)
ACCESSION NBR: xI'2081801'78 DQC. DATE: 92/08/12 NOTARIZED:
NO FACIL: 50-335 St.
Lucie Plant>
Unit 1~
Flov ida Poeer 5 Light Co.
AUTH. MANE AUTHOR AFFlLIATIQN SAGER'. *.
Flov ida Poeer 8< Light Co.
RECIP. MANE RECIPIENT AFFILIATION Document Control Bv anch (Document Contv ol Desk)
DOCKET 0 05000335
SUBJECT:
Forwards response to Rev 2 to NRC safety evaluationx transmitted via x7'20226 ltr v e relief v equest anomalies in inservice testing program. Desc'ription of pv ocess used in developing insev vice testing program also encl.
DXSTRXSLITXDN CODE:
R0470 CDPXES RECEXVED:LTR I
ENCL i
SXXE:
TITLE:
QR Submittal:
Xnservice Inspection/Testing/Relief from ASNE Code RECIPIENT lD CODE/MANE PD2-2 LA NQRRISx J INTERNAL:
ACRS NRR/DET/ENEB 7E QC/LFNB 01 CQPXES LTTR ENCL 1
0 2
2 6
6 0
REC XP XENT ID CODE/MANE PD2-2 PD NRR/DET/ECNB 9H NUDOCS-ABSTRACT OGC/HDS3 RES NILLNANiG COP IES LTTR ENCL 1
1 1
1 1
0 D
EXTERNAL:
EGSG BRQNNx B NRC PDR EGS.G RANSQNEi C NSXC NOTE TO ALL"RIDS" RECIPIENTS:
D PLEASE HELP US TO REDUCE iVAFK!CONTACT THE DOCUMENT CONTROL DESK, ROOM P !-37 (EiY'f.~i9) TO ELIMINATEYOUR NAViEI7iOiVIDISTRIBUTION LISTS FOR DCCUMEi%S YOU DON'T blEED!
TOTAL NUNBER OF COPIES REQUIRED:
LTTR 22 ENCL 19
P.O. Box 128, Ft. Pierce, FL 34954-0128 August 12, 1992 L-92-224 10 CFR 50.4 U.
S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.
C.
20555 Re:
St. Lucie Unit 1 Docket No. 50-335 NRC TAC NO. M74794 Additional Information In-Service Testin Pro ram Revision 2
On February 26,
- 1992, the NRC transmitted the safety evaluation (SE) for revision 2 of the St.
Lucie Unit 1 in-service testing program (IST).
The SE identified a
number of relief request anomalies which required additional information from Florida Power and Light company (FPL).
The NRC requested FPL to provide the additional'nformation within 180 days of the SE.
In addition, the NRC requested FPL to provide, within one year of the SE date, a
description of the process used in developing the IST program.
Attachment 1 provides the additional information requested on the relief requests.
Attachments 2 and 3 provide a description of the process used in developing the IST program.
Please contact us if there are any questions about this submittal.
Very truly yours, D. A Vice ager
- esident, St. Lucie Plant DAS/GRM/kw cc:
Stewart D. Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St. Lucie Plant DAS/PSL 8750-92 9208i80198 9208i2 PDR ADQCK 05000335 P
fi k
L,~PQ)((< >
St. Lucie Unit 1 Docket No. 50-335
'g
"'RC TAC NO. M74794 Additional Information In-Service Testin Pro ram Revision 2
ATTACHMENT I ADDITIONAL INFORMATION ON RELIEF REQUESTS A
endix B
Item 6
Relief Re uest VR">>5:
gl VR-5 requests relief from measuring and% assigning individual valve leak rate limits, per Section XI, Paragraphs IWV-3426 and IWV-3427, to several containment isolation valves (CIVs) listed in the IST program.
The licensee proposes to leak test and evaluate them in groups.
NRC Evaluation:
h Based on the determination that compliance with the Code is impracticable and burdensome, and considering the proposal, relief should be 'granted from individually testing valves that can be practically tested only in groups, with the following provisions.
The group leakage rate limits should be assigned, conservatively based on the smallest valve in the group, so that corrective action will be taken whenever the leak tight integrity of any group tested valve is in question.
Relief should be denied for those valves that can be tested individually.
The licensee should revise their procedures, as necessary to be consistent with this approach.
St. Lucie Res onse:
Individual leakage rate tests are impractical in 14 cases due to
" the configuration of the system piping and components.
In these 14
- cases, the leakage rate tests must be performed with the test volume located between the two'alves while the combined leakage rate is measured.
In each of the 14 valve pairs (see list below),
the two valves are equal in size and type, and the leakage limit is in proportion to the size.
The leakage limits are controlled by procedure.
The leakage limits are conservative such that excessive leakage through any individual valve, even the smallest, would be detected and the appropriate corrective'"action taken.
Valve Nos.
V-18794
& V-18796 FCV-25-4
& FCV-25-5 FCV-25-2
& FCV-25-3 HCV-14-1
& HCV-14-7 HCV-14-2
& HCV-14-6 V-3463
& V-07009 LCV-07-11A & LCV-07-11B V-07206
& V-07189 V-07170
& V-07188 V-00140
& V-00143 V-00139
& V-00144 V-25-11
& V-25-12 V-25-13 and V-25-14 V-25-15
& V-25-16 Pen g
10 23 24 41 42 46 47 52d 52e 56 57 58 Valve Size 2 inch 48 inch 48 inch 8 inch 8 inch 2 inch 2 inch 3 inch 3 inch 1 inch 3/8 inch 3 inch 3 inch 3 i.nch Type Globe Butfly Butfly Butfly Butfly Globe Globe Gate Gate Globe Globe Gate Gate Gate A
endix B
Item 9
Relief Re uest VR-33:
VR-33 requests relief from measuring the stroke time of power-operated valves HCV-3618, HCV-3628, HCV-3638, and HCV-3648, the flow control valves in the safety injection check valve test
- lines, per Section XX, Paragraph XWV-3413(b).
The licensee proposes to verify proper operation during exercising and fail-safe testing at. cold shutdown by direct observation.
Stroke times will not be =measured.
NRC Evaluation:
Based on the determination that complying with the Code requirements is impractical and burdensome and considering the licensee proposal, relief should be granted for an interim period of one year or until the next refueling
- outage, whichever is longer.
During this period, the licensee should develop a method of accurately measuring stroke time or some other means to adequately monitor valve condition.
St. Lucie Res onse:
The safety injection tank loop check valve leakage valves, HCV-3618 through 3648, were originally submitted for cold shutdown testing.
They have since been moved to quarterly testing on data sheet 8B of AP 1-0010125A.
Each valve is tested by pulling the fuse which supplies the power to its air solenoid.
When the air solenoid is de-energized, air is vented off of the valve positioner and the valve fails open.
On Unit 1, these valves each have a separate power supply for their position indication circuits.
They can be timed remotely instead of having to perform a containment entry.
Therefore, current testing is in accordance with ASME Section XI and relief is no longer required.
A endix B
Item 12 - Relief Re uest VR-26:
VR-26 requests relief from measuring stroke times for SE-59-1A and
-1B, the solenoid operated isolation valves in the diesel fuel oil transfer
- lines, per Section XI, Paragraph IWV-3413(b).
The licensee proposes to observe them locally during quarterly pump testing and monitor for audible noise or vibration.
Individual valve stroke times will not be measured.
NRC Evaluation:
Based on the determination that the proposal provides a reasonable short, but not a long term alternative to the Code and considering the proposal, interim relief should be granted for one year or until the next refueling outage, whichever is longer.
During this
- period, the licensee should develop a
method of accurately measuring stroke time or some other means to adequately monitor valve condition.
St. Lucie Res onse The diesel generator day tank fillvalves, SE-59-1A and SE-59-1B, are totally enclosed solenoid valves.
Because these valves are
- enclosed, there are no practical means presently available to monitor their position.
- Secondly, these valves are "quick acting" valves and therefore are not subject to stroke time trending.
All that the non-intrusive testing would tell St.
Lucie is that the valve has opened and then shut.
The same information is already obtained by physically observing the valve during operation (eg.
no unusual vibration or noise) and that the diesel generator day tanks are maintained within their proper level band.
St. Lucie relies on technologies developed by the industry for advances in valve testing.
St.
Lucie is evaluating the use of ultrasonic,
- acoustic, and eddy-current testing for non-intrusive testing of check valves.
At
- present, St. Lucie has only evaluated one type of check valve, a 2-inch piston check, using the above mentioned techniques.
Although the results from the tests were positive, they were not conclusive and could not be applied to other types of valves.
'Further investigations on other valve types are planned.
St.
Lucie will continue to test each of the diesel generators monthly.
Once each quarter during the diesel generator tests, each valve will be observed as it cycles through at least one complete cycle.
A endix B Item 13 Relief Re uest VR-24:
VR-24 requests relief from verifying individual closure for hydrogen analyzer nitrogen supply check valves, V-29305 and -29306, per Section XI, Paragraph IWV-3522(a).
The licensee proposes to test them simultaneously in the closed direction to verify at least one valve of the pair closes.
NRC Evaluation:
Based on the determination that compliance with the Code requirements is impractical and burdensome, and considering the proposal, relief should be granted provided that if excessive back flow through the pair is
- observed, both valves are declared inoperable and repaired or replaced before being return to service.
The licensee might consider the use of non-intrusive techniques to individually verify the closure of these valves.
St. Lucie Res onse:
Check valves V-29305 and V-29306 are located in the N~ zero gas supply to the Unit 1 hydrogen analyzers.
The N, zero gas system was designed to purge the hydrogen analyzer containment sample lines following an accident sample in order to reduce the local radiation levels in the reactor auxiliary building (FUSAR 6.2.5.2.3).
These two check valves were placed in series in the supply line to act as both seismic boundary and back flow prevention.
The two check valves are presently back flow tested each quarter.
Should the check valves fail the back flow test then both will be declared inoperable and evaluated for acceptability. If found unacceptable, then both will be repaired or replaced.
A endix B
Item 14 Relief Re uest VR-35:
VR-35 requests relief from measuring the stroke times of power-operated valves in the intake cooling water system, TCV-14-4A and
-4B, per Section XI, Paragraph IWV-3413(b).
The licensee proposes to monitor them locally to verify proper valve operation.
Stroke times will not be measured.
NRC Evaluation:
Based on the determination that complying with code requirements is impractical and burdensome and considering the proposal, relief should be granted for an interim period of one year or until the next refueling outage, whichever is longer.
During this period, the licensee should develop a method of accurately measuring stroke time or some other means to adequately monitor valve condition.
St. Lucie Res onse:
- Valves, TCV-14-4A and TCV-14-4B, have been placed in the IST program in response to position 11 of the NRC Generic Letter 89-04:
control valves that, have a required fail-safe position.
The valves are temperature control valves that control the intake cooling water flow rate through each of the component cooling water (CCW) heat exchangers.
The position of each valve is controlled via an air signal sent from its associated controller that monitors CCW outlet temperature.
To stroke test each valve, its control air must be isolated and manually bled off.
The rate at which the control air is bled off is dependent upon each operator that performs the test.
The variance in the bleed off times directly affect the valve stroke times.
Therefore, St. Lucie proposes to continue to stroke test these valves and measure their stroke times.
The stroke times will not be subject to alert limits but will be subject to a
maximum stroke time.
Should the measured stroke time of a'alve exceed the maximum allowed stroke time, it would be declared inoperable and would be repaired or replaced.
A endix B
Item 15 Relief Re uest Various:
Valve relief requests VR-12,
-17,
-19,
-20,
-22,
-29,
-30, and VR-31 are for check valves which cannot practically be full-stroke exercised open with system.flow per NRC GL 89-04, Position 1.
The licensee proposes to full-stroke exercise these valves by sample disassembly, inspection, and a manual exercise per NRC GL 89-04, Attachment 1, Item 2.
I r
NRC Evaluation:
Disassembly and inspection, to verify the full-stroke open capability of check valves is an option only where exercising cannot be practically performed by flow or by other positive means.
The NRC staff considers valve disassembly and inspection to be a
maintenance procedure that is not equivalent to the exercising produced by fluid flow.
This procedure has some risk which may make its routine use as a substitute for testing undesirable.
Check valve disassembly is a valuable maintenance tool that can provide,a great deal of information about a
valve internal condition. It should be performed under the maintenance program at a frequency commensurate with the valve type and service.
The use of non-intrusive techniques in conjunction with partial-stroke exercising is considered an acceptable means of verifying that a valve full-stroke exercises open.
The licensee should investigate the use of non-intrusive diagnostic techniques to demonstrate whether or not check valves swing full open during partial-stroke exercising.
If the licensee investigation reveals that full-stroke exercising with flow is not feasible, then disassembly and inspection may be used as an alternative.
The licensee must perform this procedure in accordance with GL 89-04 and should ascertain proper reassembly by performing a partial-stroke exercise or leak rate test prior to returning a valve to service.
St. Lucie Res onse:
VR-12 Safet In'ection Tank Dischar e Check Valves Full-stroke exercising of these valves would require injecting from a
tank under nominal pressure into a de-pressurized reactor coolant system.
The expected maximum peak flow rate through these valves would be approximately 20,000 gallons per minute due to a large break LOCA.
The required conditions to perform such a
full-stroke exercising of these valves is not possible.
Position 2 of the GL 89-04 had even recognized this fact.
Position 2
states:
"for some check
- valves, licensees cannot practically establish or verify sufficient flow to full-stroke exercise the valves open.
Some examples of such valves are, in PNRs... and safety injection accumulator header check valves".
St. Lucie will continue to disassemble and inspect at least one of the four check valves each refueling outage.
With this schedule, all four of the check valves will be disassembled and inspected
approximately once every six years.
- However, on October 23,
- 1991, (L-91-236),
FPL submitted revision 3 of the St. Lucie Unit 1 IST program.
Revision 3 included a relief request for the six year requirement and has requested an increase to a ten year inspection program.
This request was based upon both the valve performance history in the industry and at St.
Lucie.
Past history has established that performance of back-flow leakage testing of these valves has been able to identify internal valve problems.
VR-17 Refuelin Water Stora e
Tank to Safet In'ection Suction Header Check Valves To full-flowexercise one of these two valves, V-07119 and V-07120, would require the simultaneous operation of one full train of the safety injection (SI) pumps at full runout flow.
Such a flow test is not practical since running a containment spray pump at full runout flow would require spraying down the inside of the containment building with a contaminated boric acid solution.
St.
Lucie performs multiple,partial-flow tests each quarter during testing of the SI pumps through their mini-flow recirculation lines (>100gpm).
During each refueling outage.,the check valves are again partial-stroke tested while performing full-flowexercising of the SI pump check valves
(>4,500 gpm).
It is unknown if the flow rates achieved while performing the partial-flow tests during the refueling outages is sufficient to fully open these check valves.
St. Lucie is evaluating the use'f ultrasonic,
- acoustic, and eddy-current testing for non-intrusive testing of check valves.'t present, St. Lucie has only evaluated one type of check valve, a 2-inch piston check, using the above mentioned techniques.
Although the results from the tests were
- positive, they were not conclusive and could not be applied to valves of dissimilar design.
Further investigation of other check valve types is planned, In addition to the partial-flow exercising, St. Lucie will continue to disassemble and inspect at least one of the'se two check valves each refueling outage.
Therefore, both check valves are subject to inspection approximately once every three years (18 month fuel cycle).
VR-19 Containment Sum to Safet In'ection Suction Header Check Valves Exercising these valves to any extent (full or partial flow) would require the flooding of the-containment sump and pumping from the sump to the containment spray headers and the reactor coolant system (RCS). It is both undesirable and impractical to flood the containment sump and transfer that water to the RCS or to thespray headers.
These flow paths would create significant contamination
hazards and have an adverse effect on plant chemistry.
Since flow cannot be passed through these valves, non-intrusive test methods are not applicable.
, St. Lucie will continue to disassemble and inspect at least one of these two check valves each refueling outage.
Therefore, both check valves are subject to inspection approximately once every three years.
VR-20 Containment S ra Pum to the Containment S ra Header Check Valves Exercising these valves to any extent (full or partial flow) would require the operation of the containment spray pumps discharging into the containment spray headers.
The required conditions to perform such a full-stroke exercising of these valves is not practical.
Position 2 of the GL 89-04 had recognized this fact.
Position 2 states:
"... for some check valves, licensees cannot practically establish or verify sufficient flow to full-stroke exercise the valves open.
Some examples of such valves are, in PWRs, the containment spray header check valves II
~
~
~
~
St. Lucie will continue to disassemble and inspect at least one of these two check valves each refueling outage.
Therefore, both check valves are subject to inspection approximately once every three years (18 month fuel cycle).
VR-22 Sodium H droxide Eductor Check Valves These two check valves, V-07269 and V-07270, are located in.the lines that supply the driving fluid to the sodium hydroxide (NaOH) eductors.
These lines have no flow instruments installed.
Portable ultrasonic flow meters have been evaluated for use in measuring the flow rate but have been found unreliable.
The flow measurements fluctuate too much from one test to the next.
St.
Lucie is evaluating the use of ultrasonic,
- acoustic, and eddy-current testing for non-intrusive testing of check valves.
At,
- present, St. Lucie has only evaluated one type of check valve, a
two-inch piston
- check, using the above mentioned techniques.
Although the results from the tests were positive, they were not conclusive.
Further investigations are planned.
However, until an acceptable non-intrusive test method has been fully evaluated and
- approved, these valves will continue to be disassembled and inspected.
8
\\
Pk
VR-29 HPSI Pum Mini-Flow Recirculation Check Valves The two check valves, V-3101 and V-3103, in the lA and 1B HPSI pump mini-flow recirculation lines were originally designated for valve disassembly and inspection.
- However, an acceptable flow test has been shown to work during the last Unit 2 refueling outage for the 2A and 2B LPSI pumps.
The procedure directed the opening of one of the LPSI pump mini-flow recirculation lines to the RNT while the pump was run dead headed.
This resulted in a flow path from the RCS through the suction of the LPSI pump out the mini-flow recirculation line to the RWT.
The amount, of RCS coolant pumped through this path was detected by the increase in the RWT level.
A similar flow test for the Unit 1 HPSI pumps will be evaluated during the next Unit 1 refueling outage in the spring of 1993.
Should the test not perform as planned, St. Lucie will disassemble and inspect one. of these two valves and will pursue other test methods in the future.
St.
Lucie is evaluating the use of ultrasonic,
- acoustic, and eddy-current testing for non-intrusive testing of check valves.
At
- present, St.
Lucie has only evaluated one type of check valve, a
two-inch piston
- check, using these techniques.
Although the results from the tests were positive, they were not conclusive.
Further investigations are planned.
VR-30 LPSI Pum Mini-Flow Recirculation Check Valves The two check valves in the 1A and 1B LPSI pump mini-flow recirculation lines were originally designated for valve disassembly and inspection.
- However, an acceptable flow test has been shown to work during the last Unit 2 refueling outage.
The procedure directed the opening of one of the LPSI pump mini-flow recirculation lines to the RWT while the pump was run dead headed.
This resulted in a flow path from the RCS through the suction of the LPSI pump out the mini-flow recirculation line to the RWT.
The amount of RCS coolant pumped through this path was detected by the increase in the RWT level.
A similar flow test will be evaluated during the next Unit 1 refueling outage in the spring of 1993.
VR-31 Auxiliar Feedwater Pum Mini-Flow Recirculation and Bearin Coolin Water Check Valves Valves V-9303 through V-9305 open to provide flow paths from the auxiliary feedwater pump discharge to the condensate storage tank to ensure adequate pump cooling during low flow conditions.
V-12507 opens to provide a discharge flowpath for bearing cooling water for the steam-driven auxiliary feedwater pump.
There are no installed flow instruments in these lines.
Portable ultrasonic flow meters have been evaluated for use in measuring the flow rate
but have been found unreliable.
The flow measurements fluctuate too much from one test to the next.
St.
Lucie is evaluating the use of ultrasonic,
- acoustic, and eddy-current testing for non-intrusive testing of check valves.
At
- present, St.
Lucie has only evaluated one.type of check valve, a*
two-inch piston
- check, using the above mentioned techniques.
Although the results from the tests were positive, they were not conclusive.
Further investigations are planned.
However, until an acceptable non-intrusive test method has been fully evaluated and
- approved, these valves will continue to be disassembled and inspected.
10
St. Lucie Unit 1 Docket No. 50-335 NRC TAC NO. M74794 Additional Information In-Service Testin Pro ram Revision 2
ATTACHMENT 2 INFORMATION ON IN-SERVICE TESTING PROGRAM DEVELOPMENT Section XI of the ASME Code requires that the owner of each nuclear power plant prepare and submit a "plan" for testing and inspection of systems and components under the jurisdiction of the Code and in compliance with Title 10,
,Part:
50 of the Code of Federal Regulations (Para.
50.55a).
With respect to the elements of that plan related to the testing of pumps and
- valves,Section XI, Subsections IWP and IWV specify, in general
- terms, the program scope and testing requirements needed to satisfy the Code.
In this regard, the general requirements of Paragraphs IWP-1100 and IWV-1100 form the following basic scope document as it applies to ISI Class 1, 2, and 3.
Specifically components to be included are:
Centrifugal and positive displacement pumps that are required to perform a specific function in shutting down the reactor or in mitigating the consequences of anr,accident and that are provided with an emergency power source, and t
Valves (and their actuating and position indicating systems) which are required to perform a specific function in shutting down the reactor to the cold shutdown condition or in mitigating the consequences of an accident.
The general Code requirements were applied to St.
Lucie Unit 1
using a systematic approach by first reviewing the function of each of the plant systems as they relate to a limited number of bounding accident scenarios.
This review eliminated systems (and associated components) that clearly do not fit the basic Code definitions including that of ISI boundary classification.
- Next, a series of rules or guidelines were developed that established the criteria to be used during the review of the remaining systems and components.
These rules establish the policies and assumptions that were applied to the foregoing analysis to ensure consistency.
From this point, in a series of steps, each of the individual components in each of the remaining significant safety systems (and supporting systems) were evaluated with respect to the function of 'each component and the need for its operability as it relates to the scope of Section XI.
These steps included:
1 ~
A review of flow diagrams of each system and identification of any components (pumps or valves) that "could" potentially be included in the IST program scope.
Based on experience, valves used for maintenance isolation,
- vents, drains, etc.
were excluded.
Typically, all pumps, power-operated
- valves, check valves, and safety valves remained in the population designated for further evaluation.
2 ~
Each system was broken down by component and, based on general system operational requirements, a narrative description of each component's safety function(s) during the proposed scenarios was drafted.
3
~
Sequentially, plant documents that refer or discuss safety-related component or system functions were reviewed in detail and information from these documents was compared to the drafts developed in the above step 2.
Where appropriate, corrections and references were applied to the individual narratives.
Documents reviewed included the following:
a ~
b.
c ~di e.f.
g';
Updated Final Safety Analysis Report Technical Specifications Plant System Descriptions (Training)
Documents Special analyses Commitment correspondence Plant Operating Procedures Emergency Operating Procedures Appendix J Leakrate Test Program 4 ~
Based on the finalized component safety function evaluation derived from the document review and the corrected narratives, the IST program testing requirements were then established by applying the rules listed in Attachment 3 to each one.
5.
The functional description of the system components 'were subjected to a comprehensive review by knowledgeable plant personnel to confirm the accuracy on the document.
I
St. Lucie Unit 1 Docket No. 50-335 NRC TAC NO. M74794 Additional Information In-Service Testin Pro ram Revision 2
ATTACHMENT 3 IST PROGRAM TESTING REQUIREMENT RULES The IST program must include those pumps and valves that. perform a specific function in shutting down the reactor including cooldown to cold shutdown or in mitigating the consequences of an accident.
In this
- regard, the following guidelines are set forth for evaluation of system components (pumps and valves) with respect to their inclusion in the St.
Lucie Unit 1 IST Program and to what extent testing will be performed.
Where multiple components are capable of performing the same equivalent and redundant specified function (eg.
multiple valves closing in series) and where the components are not supplied by alternate and redundant power supplies, only one need be included in the program.
The component must be relied upon to perform and not simply have the capability of performance.
This exemption only applies where licensing documents do not take credit for the designed redundancy.
Components performing redundant function shall be included in the testing program if, in the process of analysis or licensing justification, they are relied upon to be operable.
2 ~
The St. Lucie Unit 1 FUSAR and related design basis documents shall be the primary references for determining which components are required to perform specified functions related to the spectrum of predicated accidents.
Although several other plant source documents
(
Tech.
Specs.
and EOP's) identify various components that may be important to plant safety or are to be operated in conjunction with recovery from an accident, unless specific credit, is taken in the plant safety analysis (or is implied in the analysis) for a pump or valve, the component need not be included in the IST program.
The exceptions to this are those cases where the NRC imposes test requirements at their discretion.
3.
Valves installed primarily for the purpose of providing convenient operational flexibility(eg. system cross-connects) and are not required to operate assuming that the designated first-line systems and components operate satisfactorily, need not be included in the IST program.
This does not exclude active valves that could be called upon as a result of optional system lineups existing prior to the initiation of an accident.
4 ~
Valves that are actuated as a result of a safety system automatic response shall be included in the IST program to the extent that the testing shall verify valve operation required as a result of the safety system input.
This applies only if valve movement is required to support those functions required as specified by the Code.
This requirement extends only to testing defined by the Code and is not intended to imply the need for verifying valve response to automatic logic system output.
5.
Valves whose sole function is to provide system or component redundancy related to failure of passive components need not be included if a set of all of the active components (pumps and valves) needed to fulfillthe specified system (train) function are tested double or unrelated simultaneous failures need not be assumed.
In some cases where protection of critical systems from passive failures is a
commitment, then components are included in the testing program.
6.
System safety/relief valves shall be included except where the function of the valve is solely to provide overpressure protection of an isolated component due to thermal expansion of the*internally contained fluid or a valve is installed only as a response to construction code requirements.
In the case of safety/relief valves installed on process lines that penetrate primary containment and could be isolated during an accident, if an overpressure condition could be created within the piping at the penetration such that the structural integrity of the containment could be jeopardized, then the valve should be setpoint tested.
7.
All valves included in the St. Lucie Unit 1 leakrate testing program complying with 10 CFR 50, Appendix J shall be included in the IST program as Category A valves.
8.
All valves designated as high-low pressure interface valves (pressure isolation valves) shall be included in the IST program as Category A valves.
9.
Any active Category A valve shall be designated for testing (exercising) to the closed direction.
10.
When the normal valve position during operation is its position required to perform its designated safety function and valve movement may be required due to plant evolutions or possible repositioning during accident response or recovery operations, then periodic exercising per the Code is required (ie. the valve cannot be considered passive).
Where an air-operated valve is provided with a
simple air-pilot valve, the pilot valve need not be specifically included in the IST program provided that the testing
e E
performed on the main valve verifies the proper operation of the pilot valve.
12.
Control valves are specifically excluded from testing per IWV-1200(a); however, if a control valve must change position to support a safety-related function and it has a fail-safe
- position, then it must.
be included in 'the IST program and tested to the extent practical.
Steam turbine governor valves are considered to be an integral part of the turbine and, as
- such, are not included in the IST program.
13.
Check valves are included where a valve serves as the only effective boundary between piping associated with a necessary safety function and non-safety grade (non-seismic) piping.
Failure of passive system components is assumed only for non-safety grade systems.
14.
Where a valve performs a safety function in both directions (open and closed) exercising in both direction is required as described in Reference 1.
For these power-operated
- valves, stroke time measurements in both directions would be required.
15.
Pumps and valves whose only safety function is predicated on plant shutdown and recovery from a fire per commitment made as a result on 10 CFR 50, Appendix R are not included in the IST program.
16.
Pumps and valves that are not categorized as ISI Class 1,
2, or 3 need not be included in the IST program.
17.
Check valves that have a safety function to close should be evaluated with respect to categorization as Category A/C versus C with respect to the following issues:
a ~
Whether the flow requirements for connected systems can be achieved with the maximum possible leakage through the check valve.
b.
The effect on the performance of other components and systems due to the reduced flow resulting from the leakage.
c ~
The consequences of loss of fluid from the system.
d.
The effect that backflow through a valve may have on piping and components, such as the effect of high temperature and thermal stresses.
e.
The radiological exposure to plant personnel and the public caused by the leak.